What job do the lungs perform in eliminating wastes from the body?

The lungs are part of the excretory system in that they eliminate carbon dioxide from the body by expiration or breathing out. The blood is taken to the lungs by the pulmonary artery, where the blood cells enter the alveoli and exchange carbon dioxide with oxygen gas, as it travels around the body again, the lungs push the carbon dioxide out of the body as one exhales.